summaryrefslogtreecommitdiff
path: root/tex/context/base/mkiv/toks-scn.lua
blob: f73ecc86c50d5e8888fafd1491bc944770f17a17 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
if not modules then modules = { } end modules ['toks-scn'] = {
    version   = 1.001,
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

-- Writing this kind of code (and completing the newtoken code base) is fun. I did
-- so with the brilliant film music from The Girl with the Dragon Tattoo running in a
-- loop in the background (three cd's by Trent Reznor and Atticus Ross). An alien
-- feeling helps with alien code.

-- todo: more \let's at the tex end

local type, next, tostring, tonumber = type, next, tostring, tonumber

local formatters     = string.formatters
local concat         = table.concat

local scanners       = tokens.scanners
local tokenbits      = tokens.bits

local scanstring     = scanners.string
local scanargument   = scanners.argument
local scaninteger    = scanners.integer
local scannumber     = scanners.number
local scankeyword    = scanners.keyword
local scankeywordcs  = scanners.keywordcs
local scanword       = scanners.word
local scancode       = scanners.code
local scanboolean    = scanners.boolean
local scandimen      = scanners.dimen
local scancsname     = scanners.csname

local todimen        = number.todimen
local toboolean      = toboolean

local lpegmatch      = lpeg.match
local p_unquoted     = lpeg.Cs(lpeg.patterns.unquoted)

local trace_compile  = false  trackers.register("tokens.compile", function(v) trace_compile = v end)
local report_compile = logs.reporter("tokens","compile")
local report_scan    = logs.reporter("tokens","scan")

local open  = tokenbits.open
local close = tokenbits.close

local function scanopen()
    while true do
        local c = scancode(open)
        if c == 123 then
            return true
     -- elseif c ~= 32 then
        elseif not c then
            return
        end
    end
end

local function scanclose()
    while true do
        local c = scancode(close)
        if c == 125 then
            return true
     -- elseif c ~= 32 then
        elseif not c then
            return
        end
    end
end

scanners.scanopen  = scanopen
scanners.scanclose = scanclose

local function scanlist()
    local wrapped = scanopen()
    local list    = { }
    local size    = 0
    while true do
        local entry = scanstring()
        if entry then
            size = size + 1
            list[size] = entry
        else
            break
        end
    end
    if wrapped then
        scanclose()
    end
    return list
end

local function scanconditional()
    local kw = scanword()
    if kw == "true" then
        return true
    end
    if kw == "false" then
        return false
    end
    local c = scaninteger()
    if c then
        return c == 0 -- with a conditional 0=true
    end
    return nil
end

local function scantable(t,data)
    if not data then
        data = { }
    end
    local wrapped = scanopen()
    while true do
        local key = scanword()
        if key then
            local get = t[key]
            if get then
                data[key] = get()
            else
                -- catch all we can get
            end
        else
            break
        end
    end
    if wrapped then
        scanclose()
    end
    return data
end

function tokens.constant(s)
    if type(s) == "string" then
        return "'" .. s .. "'"
    else
        return s
    end
end

scanners.list        = scanlist
scanners.table       = scantable
scanners.conditional = scanconditional

local shortcuts = {
    tokens          = tokens,
    bits            = tokenbits,
    open            = open,
    close           = close,
    scanners        = scanners,
    scanstring      = scanstring,
    scaninteger     = scaninteger,
    scannumber      = scannumber,
    scantable       = scantable,
    scankeyword     = scankeyword,
    scankeywordcs   = scankeywordcs,
    scanword        = scanword,
    scancode        = scancode,
    scanboolean     = scanboolean,
    scandimen       = scandimen,
    scandimension   = scandimen,
    scanconditional = scanconditional,
    scanopen        = scanopen,
    scanclose       = scanclose,
    scanlist        = scanlist,
    scancsname      = scancsname,
    todimen         = todimen,
    tonumber        = tonumber,
    tostring        = tostring,
    toboolean       = toboolean,
    inspect         = inspect,
    report          = report_scan,
}

tokens.shortcuts = shortcuts

local load = load
local dump = string.dump

local function loadstripped(code)
     return load(code,nil,nil,shortcuts)
  -- return load(dump(load(code),true),nil,nil,shortcuts)
end

tokens.converters = {
    tonumber  = "tonumber",
    tostring  = "tostring",
    toboolean = "toboolean",
    todimen   = "todimen",
    toglue    = "todimen",
}

-- We could just pickup a keyword but then we really need to make sure
-- that no number follows it when that is the assignment and adding
-- an optional = defeats the gain in speed. Currently we have sources
-- with no spaces (\startcontextdefinitioncode ...) so it fails there.
--
-- Another drawback is that we then need to use { } instead of ending
-- with \relax (as we can do now) but that is no big deal. It's just
-- that I then need to check the TeX end. More pain than gain and a bit
-- risky too.

local f_if       = formatters[    "  if scankeywordcs('%s') then data['%s'] = scan%s()"]
local f_elseif   = formatters["  elseif scankeywordcs('%s') then data['%s'] = scan%s()"]

----- f_if       = formatters["  local key = scanword() if key == '' then break elseif key == '%s' then data['%s'] = scan%s()"]
----- f_elseif   = formatters["  elseif key == '%s' then data['%s'] = scan%s()"]

----- f_if_x     = formatters[    "  if not data['%s'] and scankeywordcs('%s') then data['%s'] = scan%s()"]
----- f_elseif_x = formatters["  elseif not data['%s'] and scankeywordcs('%s') then data['%s'] = scan%s()"]

local f_local    = formatters["local scan%s = scanners.%s"]
local f_scan     = formatters["scan%s()"]
local f_shortcut = formatters["local %s = scanners.converters.%s"]

local f_if_c     = formatters[    "  if scankeywordcs('%s') then data['%s'] = %s(scan%s())"]
local f_elseif_c = formatters["  elseif scankeywordcs('%s') then data['%s'] = %s(scan%s())"]
local f_scan_c   = formatters["%s(scan%s())"]

-- see above
--
----- f_if_c     = formatters["  local key = scanword() if key == '' then break elseif key == '%s' then data['%s'] = %s(scan%s())"]
----- f_elseif_c = formatters["  elseif k == '%s' then data['%s'] = %s(scan%s())"]

local f_any      = formatters["  else local key = scanword() if key then data[key] = scan%s() else break end end"]
local f_any_c    = formatters["  else local key = scanword() if key then data[key] = %s(scan%s()) else break end end"]
local s_done     = "  else break end"

local f_any_all  = formatters["  local key = scanword() if key then data[key] = scan%s() else break end"]
local f_any_all_c= formatters["  local key = scanword() if key then data[key] = %s(scan%s()) else break end"]

local f_table    = formatters["%\nt\nreturn function()\n  local data = { }\n%s\n  return %s\nend\n"]
local f_sequence = formatters["%\nt\n%\nt\n%\nt\nreturn function()\n    return %s\nend\n"]
local f_simple   = formatters["%\nt\nreturn function()\n    return %s\nend\n"]
local f_string   = formatters["%q"]
local f_action_f = formatters["action%s(%s)"]
local f_action_s = formatters["local action%s = tokens._action[%s]"]
local f_nested   = formatters["local function scan%s()\n  local data = { }\n%s\n  return data\nend\n"]

-- local f_check = formatters[ [[
--   local wrapped = false
--   while true do
--     local c = scancode(open)
--     if c == 123 then
--       wrapped = true
--       break
--     elseif c ~= 32 then
--       break
--     end
--   end
--   while true do
--     ]] .. "%\nt\n" .. [[
--     %s
--   end
--   if wrapped then
--     while true do
--       local c = scancode(close)
--       if c == 125 then
--         break
--       elseif c ~= 32 then
--         break
--       end
--     end
--   end
-- ]] ]

local f_check = formatters[ [[
  local wrapped = scanopen()
  while true do
    ]] .. "%\nt\n" .. [[
    %s
  end
  if wrapped then
    scanclose()
  end
]] ]

-- using these shortcuts saves temporary small tables (okay, it looks uglier)

local presets = {
    ["1 string" ] = { "string" },
    ["2 strings"] = { "string", "string" },
    ["3 strings"] = { "string", "string", "string" },
    ["4 strings"] = { "string", "string", "string", "string" },
    ["5 strings"] = { "string", "string", "string", "string", "string" },
    ["6 strings"] = { "string", "string", "string", "string", "string", "string" },
    ["7 strings"] = { "string", "string", "string", "string", "string", "string", "string" },
    ["8 strings"] = { "string", "string", "string", "string", "string", "string", "string", "string" },
}

tokens.presets = presets

function tokens.compile(specification)
    local f = { }
    local n = 0
    local c = { }
    local t = specification.arguments or specification
    local a = specification.actions or nil
    if type(a) == "function" then
        a = { a }
    end
    local code
    local function compile(t,nested)
        local done = s_done
        local r = { }
        local m = 0
        for i=1,#t do
            local ti = t[i]
            if ti == "*" and i == 1 then
                done = f_any_all("string")
            else
                local t1 = ti[1]
                local t2 = ti[2] or "string"
                if type(t2) == "table" then
                    n = n + 1
                    f[n] = compile(t2,n)
                    t2 = n
                end
                local t3 = ti[3]
                if type(t3) == "function" then
                    -- todo: also create shortcut
                elseif t3 then
                    c[t3] = f_shortcut(t3,t3)
                    if t1 == "*" then
                        if i == 1 then
                            done = f_any_all_c(t3,t2)
                            break
                        else
                            done = f_any_c(t3,t2)
                        end
                    else
                        m = m + 1
                        r[m] = (m > 1 and f_elseif_c or f_if_c)(t1,t1,t3,t2)
                    end
                else
                    if t1 == "*" then
                        if i == 1 then
                            done = f_any_all(t2)
                            break
                        else
                            done = f_any(t2)
                        end
                    else
                        m = m + 1
                        r[m] = (m > 1 and f_elseif   or f_if  )(t1,t1,t2)
                     -- r[m] = (m > 1 and f_elseif_x or f_if_x)(t1,t1,t1,t2)
                    end
                end
            end
        end
        local c = f_check(r,done)
        if nested then
            return f_nested(nested,c)
        else
            return c
        end
    end
    local p = t and presets[t] -- already done in implement
    if p then
        t = p
    end
    local tt = type(t)
    if tt == "string" then
        if a then
            local s = lpegmatch(p_unquoted,t)
            if s and t ~= s then
                code = t
            else
                code = f_scan(t)
            end
            tokens._action = a
            for i=1,#a do
                code = f_action_f(i,code)
                n    = n + 1
                f[n] = f_action_s(i,i)
            end
            code = f_simple(f,code)
        else
            return scanners[t]
        end
    elseif tt ~= "table" then
        return
    elseif #t == 1 then
        local ti = t[1]
        if type(ti) == "table" then
            ti = compile(ti)
            code = "data"
            if a then
                tokens._action = a
                for i=1,#a do
                    code = f_action_f(i,code)
                    n    = n + 1
                    f[n] = f_action_s(i,i)
                end
            end
            code = f_table(f,ti,code)
        elseif a then
            code = f_scan(ti)
            tokens._action = a
            for i=1,#a do
                code = f_action_f(i,code)
                n    = n + 1
                f[n] = f_action_s(i,i)
            end
            code = f_simple(f,code)
        else
            return scanners[ti]
        end
    else
        local r = { }
        local p = { }
        local m = 0
        for i=1,#t do
            local ti = t[i]
            local tt = type(ti)
            if tt == "table" then
                if ti[1] == "_constant_" then
                    local v = ti[2]
                    if type(v) == "string" then
                        r[i] = f_string(v)
                    else
                        r[i] = tostring(v)
                    end
                else
                    m = m + 1
                    p[m] = compile(ti,100+m)
                    r[i] = f_scan(100+m)
                end
            elseif tt == "number" then
                r[i] = tostring(ti)
            elseif tt == "boolean" then
                r[i] = tostring(ti)
            else
                local s = lpegmatch(p_unquoted,ti)
                if s and ti ~= s then
                    r[i] = ti -- a string, given as "'foo'" or '"foo"'
                elseif scanners[ti] then
                    r[i] = f_scan(ti)
                else
                    report_compile("unknown scanner %a",ti)
                    r[i] = ti
                end
            end
        end
        code = concat(r,",")
        if a then
            tokens._action = a
            for i=1,#a do
                code = f_action_f(i,code)
                n    = n + 1
                f[n] = f_action_s(i,i)
            end
        end
        code = f_sequence(c,f,p,code)
    end
    if not code then
        return
    end
    if trace_compile then
        report_compile("code: %s",code)
    end
    local code, message = loadstripped(code)
    if code then
        code = code() -- sets action
    else
        report_compile("error in code: %s",code)
        report_compile("error message: %s",message)
    end
    if a then
        tokens._action = nil
    end
    if code then
        return code
    end
end

-- local fetch = tokens.compile {
--     "string",
--     "string",
--     {
--         { "data",    "string" },
--         { "tab",     "string" },
--         { "method",  "string" },
--         { "foo", {
--             { "method", "integer" },
--             { "compact", "number" },
--             { "nature" },
--             { "*" }, -- any key
--         } },
--         { "compact", "string", "tonumber" },
--         { "nature",  "boolean" },
--         { "escape",  "string" },
--         { "escape"  },
--     }
--     "boolean",
-- }
--
-- os.exit()